The present invention relates to a process for the preparation of aromatizing compositions, more particularly the biogeneration of mixtures comprising compounds being able to develop or enhance typical baked type aroma upon heating.
Fresh bread-like aroma is one of the most important criteria of the quality of bakery products and such flavor reflects the freshness of the product. For packaged, chilled and frozen bakery products such as pizza, bread-rolls, croissants, crusts for example, this flavor is often weak mainly because of processing/storage of these products and thus the overall quality of the final product after heating or baking is generally perceived as not close to that of traditional freshly made products.
The bread-like aroma is composed of a complex mixture of odorant compounds identified in the crust of baguette (Zehentbauer G. and Grosh W., 1998. Journal of Cereal Science 28, 81-92.) such as 2-acetyl-1-pyrroline, 2-acetyl-2-thiazoline and pyrazines (responsible for roasted note), furanones (responsible for caramel-like note), ketones and diketones (responsible for buttery note) and aldehydes (responsible for malty note), for example.
Several methods are known to prepare bread-type aromatizing compositions mainly based on Maillard reaction and/or fermentation.
U.S. Pat. No. 4,663,168 discloses a method for preparing a heat-stable yeast fermented malt reaction flavor concentrate from a mixture of malt flour, yeast and fermentable sugar. The method comprises the steps of fermenting a mixture of malt flour by yeast, heating the fermented malt to produce the flavor and inactivating the yeast. The flavor obtained is described as bread crust-like, nutty and toasted grain.
Japanese patent application 7-242,661 discloses the preparation of dimethyl-pyrrolidinyl-furanone and its use for imparting or increasing freshly baked or boiled flavor of bakery foods.
U.S. Pat. No. 6,432,459 describes a process for preparing an aromatizing composition containing 2-acetyl-2-thiazoline and its precursors involving bioconversion of a sulfur containing compound and an organic acid or its derivative in the presence of yeast, separation and recovery of the supernatant. This composition is presented as being able to enhance the roasted notes of bakery products.
U.S. Pat. No. 5,262,189 discloses the use of carbomethoxy-2-pyrroline-1 as aromatizing agent to impart cereal or bread-crust aroma to product in which it is incorporated.
European Patent application 937,402 describes a composition for intensifying the browning and the aroma of baked goods and comprises ascorbic acid, an amino acid, a carbohydrate and a phosphate and optionally lactic acid. This composition is intended to be sprayed onto pre-baked goods and thus both improves the appearance (browning) and intensifies the aroma.
All the previous works already done mainly focused on roasted aroma and moreover the aromatizing compositions obtained were not fully balanced in the different typical aromas and flavors responsible for the global baked aroma. Moreover some of the previous methods were based on pure chemical reaction that is not always desired for food products. Thus, improvements in these type products and their methods of manufacture are desirable.